Cellular steel floor



Nov. l5, 1954 H H, CRAFTQN 2,694,475

CELLULAR STEEL FLOOR Filed NOV. 19, 1948 2 Sheets-Sheet l L Il L L INVENTOR. M 7 BY/ e/vfy h. Crvffm Nov. 16, 1954 H. H. cRAr-'TON CELLULAR STEEL FLooR 2 Sheets-Sheet 2 Filed Nov. 19, 1948 JNVENToR. /veng/ H 'afon. BY

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United States Patent Office 2,694,475 Patented Nav. 16, 1954 2,694,475 CELLULAR STEEL FLOOR Henry H. Crafton, Baden, Pa., assignor to H. H. Robertson Company, Pittsburgh, Pa., a corporation of Penn- Sylvania Application November 19, 1948, Serial No. 60,875

2 Claims. (Cl. 189-34) This invention relates to a building construction and more particularly to a cellular steel floor construction.

The invention has for an object to provide a novel and improved floor construction embodying multicellular metal oor units having a plurality of spaced and longitudinally extended wire distributing cells and in which provision is made for connecting the units end to end in a simple and efficient manner to form end joints adapted to assure positive alignment of the cells of the connected units and in a manner such as to provide smooth and flush interior surfaces at the cell joints whereby to enable electrical conductors to be drawn through the cells without obstruction at the connecting joints.

With this general object in view and such others as may hereinafter appear, the invention consists in the floor construction hereinafter described and particularly defined in the claims at the end of this specification.

In the drawings illustrating the preferred embodiment of the invention, Fig. l is a perspective view of a cellular metal tloor unit embodying the present invention and illustrating the structure of one connecting end of the unit; Fig. 2 is a perspective View illustrating the structure of the other connecting end of the floor unit shown in Fig. l; Fig. 3 is a plan View showing the end joint formed by connecting two floor units end to end in accordance with the present invention; Fig. 4 is a perspective view, partly in cross-section, as taken on the line 4-4 of Fig. 3, and Fig. 5 is a perspective view of a modified form of a cellular .metal iioor unit embodying the present invention.

In general, the present invention contemplates a lloor construction embodying cellular metal iloor units for use in erecting a load supporting and wire distributing oor of the type illustrated in the United States Patents Nos. 1,855,082 and 1,867,433. In practice it is preferred to manufacture the cellular metal floor in units of varying lengths, and during the erection of the floor the units are laid end to end, preferably being supported upon girders so that the joints between the ends of adjacent units come over the girders and so that the cells of one unit cooperate with and form extensions of the cells of a second unit to provide a plurality of continuous ducts or conduits extending across the building and through which wiring for electrical service of various sorts may be drawn, as set forth in Patent No. 1,855,082, above referred to.

Prior to the present invention, it has been the practice to lay successive load supporting and wire distributing floor units end to end in substantially abutting relation which required careful and accurate placing of the units and maintenance of the units in their placed position while they were being secured to the structural supports to effect the desired alignment of the cells of successive units. However, in actual practice, if the units were not properly aligned, or if a space occurred between the ends of adjacent units, the unaligned or open portions of the joint caused diiliculty in fishing the wiring through the cells, the imperfect joint forming an obstruction to the fishing tool.

In accordance with the present invention, the leading and trailing ends of the multicellular floor units are particularly designed for mutual interconnection with co operating units to form an end joint arranged to assure positive alignment of the cells of the connected units and in a manner such as to provide smooth and flush interior cell surfaces at the joints to enable the wiring to be drawn through the cells without obstruction to the fishing tool or injury to the wires.

In practice the present end joint structures of the cellular wire distributing floor units may be economically and accurately manufactured in existing sheet forming machines in which the ends of the sheets are cut square in a resquaring press and in which the interconnecting end portions may be formed by suitable dies arranged to cooperate with the resquaring press whereby to assure perfectly square end portions and positive and accurate end to end alignment of the assembled units.

Referring now to the drawings, 10 represents one type of cellular metal oor used in the erection of buildings and which comprises a multicellular unit formed by assembling and uniting together, preferably by welding, an upper iiat sheet 12 and lower corrugated sheets 14, 16 to form in effect a series of closely spaced parallel hollow beams or cells 1S. In erecting the floor, the individual building units extend between the structural steel supporting elements of the building with the ends ofthe units resting on and preferably welded to the steel framework of the building herein shown as comprising girders 20, a plurality of units being laid end to end to form continuous elongated wiring cells. Adjacent units may be laid side by side and connected in interlocking relation by the cooperation of marginal lip portions 22, 24 formed on opposite sides of the upper flat sheet 12, as illustrated.

In accordance with the present invention, in order to assure positive alignment of the cells 18 and to provide smooth and flush interior cell surfaces at the connected ends, the leading and trailing ends 26, 28 of the building units are particularly designed for mutual interconnection with corresponding end portions of adjacent units, preferably in a manner such that the trailing end portion 2S of one unit may be iitted into nesting relation with the leading end portion 26 of the adjacent unit. in the illustrated embodiment of the invention, the side and top walls of the corrugated sheets 14, 16 are preferably arranged in overlapping relation and the bottom walls thereof are arranged to meet in abutting relation.

As illustrated in Fig. 2, the trailing ends 28 of the lower corrugated sheets 14, 16 are cut perfectly square, and as illustrated in Fig. l, the leading ends 26 of the corrugated sheets are provided with offset and die set portions 34, 36, 40 extending from the side walls 3d, 32 and upper walls 3S respectively of the corrugations. The bottom wall 42 of each cell is provided with a cut out portion 44, the cut back being substantially equal to the length of the oset portions, as illustrated. The die set portions 34, 36 respectively formed in the side walls 30, 32 are offset outwardly from the cell walls a distance substantially equal to the thickness of the sheet metal forming the corrugated sheets, and the die set portions 40 in the upper walls 38 are offset downwardly a similar distance. Thus, in erecting the flooring, the cell portions of the trailing end 28 may be dropped into position between the offset side wall portions 34, 36 of the leading end 26 and on top of the offset upper wall portions 40 formed between adjacent cells and with the edges of the cut out portions 44 of the bottom walls meeting in aligned and abutting relation with the ends of the bottom walls of the trailing end of the cooperating unit. The edges of the cut back portions 44 are preferably cut perfectly square in the resquaring press in order to assure accurate alignment with the abutting square cut edges of the lower walls of the trailing end 28. It will be observed that the abutting relation of the lower walls of the corrugations provide a llush undersurface for the ends of the units which are arranged to rest on and are secured to the supporting girder 20.

In erecting the flooring the ends of the units are are ranged to rest upon the structural supporting girders 20 so that the joints occur above the girders, the ends of the units being welded to the girders during the progress of the erection, and as herein shown, the upper sheet 12 of each unit is preferably shorter in length than the underlying corrugated sheets 14, 16 the ends thereof being set back a short distance from the ends of the underlying sheets in order to provide an opening along the top of lthe units above the joint, as indicated at 46 in Fig. 3,

whereby to permit access to the ends of the units to permit them to be conveniently welded to the girders 20 and also to permit inspection of the wiring in the cells during installation of the system. The opening 46 is subsequently closed by a cover plate, indicated by dot and dash lines 47 in Fig. 3, and comprising a flat strip of sheet metal of substantially the same thickness as the upper sheet 12 and which is extended across the width of the units and Welded or otherwise secured to the top walls of the corrugations and to the marginal edges 49, 51 at the joint. Thus, it will be observed that the downwardly offset disposition of the die set portions 40 permit the adjacent upper surfaces 38 of the connected units to present a ush upper surface to which the cover plates may be secured. As illustrated in Figs. 1 and 5, in order to take up some of the metal forced out of alignment with the walls of the cells during the die setting operation, the offset portions 40 in the upper walls 38 of the jcorrugations may be relieved by concave or inwardly bent portions 48. While the lower or corrugated portions of the building unit are herein shown as comprising two sections 14, 16 for convenience in manufacture, and providing a space 53 between the inner marginal edges 55, it will be understood that the two units 14, 16 may be made in one continuous section if desired.

A modified form of the invention, as illustrated in Fig. 5, is similar to the above described structure except that the upper member of the assembled building unit comprises a corrugated sheet 50 having its lower walls or connecting web portions 52 welded or otherwise secured to the upper walls 38 of the lower corrugated sheets 14, 16 to form elongated wiring cells 54. The lower corrugated sheets 14, 16 are shaped to form leading and trailing ends 26, 2S arranged for mutual interconnection with adjacent units in the manner previously described, and the upper corrugated sheet 50 may be shorter in length than the underlying corrugated sheets to provide temporary openings in the tops of the cells at the joints which are subsequently closed by suitable corrugated cover plates. It will be understood that, in practice, the proportions of the various elements may vary to provide units having either deep or shallow corrugations, and that some of the units, such as that illustrated in Fig. 1, may be erected in an inverted position.

From the above description it Will be observed that the present wire distributing floor units are provided with novel end joint structures adapted for mutual interconnections whereby to facilitate assembly of successive ooring units and to assure positive alignment of the cells of successive units, and to provide a closed joint having smooth and ush interior cell surfaces at the joint to permit electrical conductors to be drawn through the cells with minimum obstruction and minimum damage to the wiring being drawn through the cells. It will also be observed that the present joint structure presents a ush undersurface at the joint for cooperation with the underlying supporting beams or girders to which the ends of the units are attached.

While the preferred embodiment of the invention has been herein illustrated and described, it will be understood that the invention may be embodied in other forms within the scope of the following claims.

Having thus described the invention, what is claimed is:

1. In a building construction, a flooring structure comprising a plurality of multi-cellular sheet metal flooring units erected side by side and in end to end abutting relation upon a supporting framework to form the flooring, each of the ooring units comprising an upper sheet and a lower corrugated sheet secured thereto and forming spaced and longitudinally extended cells comprising wiring ducts, each corrugation including substantially straight upper, side and bottom walls, one end only of each lower sheet having outwardly extended offset portions in the side walls of the corrugations thereof and having downwardly oiset portions in the upper walls thereof, the bottom walls of the corrugations at said one end being cut back a distance substantially equal to the length of said extended offset portions, said outwardly and downwardly offset portions being offset an equal amount to the thickness of the metal of the units, the corrugations at the other end of each unit being free of oifset portions and having the tops and the sides of the corrugations thereof received by the offset top and side portions of the corrugations of a cooperating unit in nesting and over-lapping relation and having the bottom walls of the corrugations thereof in aligned and substantially abutting relation with the bottom walls of the corrugations of said cooperating unit, thereby forming a connecting joint between the units having smooth and ush side and bottom interior cell surfaces.

2. A building construction as dened in claim l wherein the upper sheet of each unit is set back from the ends of the underlying sheet thereof forming transverse openings in the erected oor above the joints between adjacent units, and elongated strip means extending over the exposed ends of the corrugations and forming a cover for said opening.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 696,737 Jones Apr. l, 1902 934,939 Schlay Sept. 21, 1909 1,799,436 Neuman Apr. 7, 1931 1,855,082 Young Apr. 19, 1932 1,867,433 Young July 12, 1932 1,904,080 Plummer et al. Apr. 18, 1933 2,041,965 Sargent May 26, 1936 2,125,366 Young et al. Aug. 2, 1938 2,259,674v Wiesmann Oct. 21, 1941 2,419,996 Honikman May 6, 1947 FOREIGN PATENTS Number Country Date 476,870 Great Britain of 1937 537,108 Great Britain of 1941 

